The growth of electronic communication, including electronic marketing and promotions, has given rise to a corresponding growth in the desire to increase the efficacy of such electronic promotions. Empirical studies have shown that the more personalized an electronic promotion is to a recipient, the greater the likelihood of receiving a response to the electronic promotion from the recipient. For example, a personalized e-mail message about an upcoming sale may be delivered to a potential customer who has expressed prior interest in one or more of the sales items. It may be the case that the greater the level of personalization of the e-mail message, the greater the likelihood of receiving a response to the e-mail message.